Equifax originally said that hackers accessed the personal information 143 million people from May 13 to July 30, 2017. According to a security firm Equifax hired to investigate the breach, hackers “roamed undetected” in the company’s network for four months before the breach. Fire Eye’s Mandiant group said this week that the hackers’ “first ‘interaction’ with the company” took place on March 10. Check out our full coverage of the Equifax hack.